This invention relates generally to food processing, including meat processing. More particularly, the invention relates to methods and devices that improve the dressing and processing of carcasses along meat processing lines.
During commercial meat production in a slaughterhouse, a carcass is subjected to a number of different procedures. An animal is first stunned and bled, its hide is removed from the resulting carcass, and the carcass is washed. The carcass may be steam pasteurized, and the carcass may also be subjected to an electrical stimulation process. Throughout this specification, the term “carcass” will be used to refer to the animal body after the animal is stunned and bled. The animal carcass is typically split into two equal halves at some point along the processing line depending on its species and the intended purpose for the carcass.
During commercial meat production, the carcass is attached to a trolley, gambrel, or shackle (hereinafter referred to as a “trolley”) at an early point along the meat processing line. A trolley may be used in a variety of embodiments. In general, the trolley includes a hook or other suitable connection device to attach the carcass to the trolley, and a roller, slide device, or wheel of the trolley travels along a rail. The trolley is typically moved along the rail either by the force of gravity or by the use of a power chain above the rail that engages the trolley and pulls it along the rail. The carcass, which is attached to and hangs from the trolley, may therefore be moved along the meat processing line and a number of processing functions may be performed at various stations along the processing line.
A meat processing line contains one or more processing line segments and one or more segments of power chains. In other words, a first power chain may pull a trolley and attached carcass through a first series of processing stations, the first power chain may then be disengaged from the trolley, and a second power chain may engage the trolley and pull the trolley through a second series of processing stations. Any number of such processing line segments and power chain segments may be used. For each segment of the power chain along the processing line, however, a stoppage of the power chain or slowing of the rate of movement of the power chain will impact the entire segment of the processing line along that power chain, thus affecting the processing rate of the carcasses. In typical meat processing lines, each power chain segment moves at the same rate.
A carcass in a slaughterhouse travels along the meat processing line and is subjected to a number of processes, including those identified above as well as weighing of the carcass and removal of some portions of the carcass. The carcasses are also inspected at a number of locations along the meat processing line, and certain information regarding carcasses is typically recorded at the inspection locations. In addition, portions of the carcass that have been removed, such as the viscera, may be inspected to ensure that the animal was healthy at the time of slaughter.
FIG. 1 is a flowchart showing the processes typically performed on a carcass moving along a meat processing line, during commercial beef production. As shown in FIG. 1, the following processes are typically performed. The animal is stunned and bled (block 10). Next, the hide is removed (block 12). The carcass is subjected to a prewashing operation (block 14). Viscera is removed and the carcass is split into two halves (block 16). The carcass is inspected (block 18). The carcass is weighed on a scale (block 20) and washed (block 22).
FIG. 1 depicts these processes of a meat processing line, as well as the chilling of the carcass (block 24) after these procedures are complete. After the carcass wash (block 22), the carcass is typically delivered to a storage chill room where the carcass is cooled prior to further processing and packaging of the meat for distribution and consumption. Of course, numerous other processes, such as trimming and removal of certain portions of the carcass, are also typically carried out before chilling of the carcass.
Although a carcass may be inspected by numerous individuals or pieces of equipment along a meat processing line for various purposes, the terms “inspection” and “inspecting,” as used throughout this specification, refer to a carcass inspection performed by either technical service personnel of the company or a government entity, such as the United States Department of Agriculture (“USDA”). Pursuant to statutory regulations or rules, an inspection of every carcass is typically performed at inspection stations located adjacent to or along the meat processing line. Usually, the inspection is performed by a person or a group of persons, and therefore human inspection creates a barrier to further mechanization and automation of a meat processing line. An inspector along a meat processing line typically looks for any bruising or contamination of a carcass, such as signs of any foreign material on the carcass, and for pathological problems, which may typically be discovered on beef carcasses through an examination of the vital organs (e.g., kidney, liver, and heart) or the lymph glands of the carcass. The transfer of bacteria from the skins of animals to meat is one problem in processing animal carcasses, and this problem has been dealt with through inspection and washing of the carcasses, including hot washes, steam pasteurization, and acid sprays.
The methods for processing and inspecting carcasses discussed above have disadvantages. First, final inspection is performed prior to the points in the meat processing line where carcasses are washed, weighed on a scale, trimmed, and steam pasteurized. As these processes involve handling of the carcasses, they may increase microbial contamination of the carcass. Thus, inspection of the carcasses prior to these processes results in a deficient inspection process. Second, because inspection is performed before weighing with a scale, portions of the carcass that are removed due to contamination, pathological problems, and/or bruising are not weighed, and as a result, no information on weight loss due to these problems can be gathered. The removal of such portions of the carcass before weighing also reduces the weight of the carcass and may therefore decrease the payment to the producer of the animal carcass, which is typically based, at least in part, on the weight of the carcass, with heavier carcasses garnering higher payments.
Additionally, inspection of the carcasses, as typically performed, may significantly slow the processing of carcasses along a meat processing line. If an inspection reveals a contaminated carcass or a carcass with some other defect, the entire processing line is shut down or slowed down in order to remove the carcass from the processing line or remove the contaminated portion from the carcass. Alternatively, at least the segment of the processing line immediately before the inspection station is shut down so that the carcass with the defect may be removed from the line. If a carcass with a defect or contamination is found, the carcass is removed from the main processing line, and it may be either recirculated after the defect has been cleared, or it may be condemned and disposed of if the defect is of a serious nature.
In meat processing lines known in the art, if the meat processing line or a segment thereof is slowed or shut off to remove a carcass at an inspection station, the entire meat processing line is affected, thus slowing the throughput of the meat processing line causing the line to operate for a longer period of time to process the same number of carcasses. Since microbial growth is dependent upon time and temperature, this time delay in processing carcasses and moving the carcasses to a chill room creates a situation in which all carcasses present on the line are subject to increased microbial growth. This potential for increased microbial growth, for which temperature conditions are optimal while a carcass is on the meat processing line, could create additional food safety concerns that may be minimized with a more consistent throughput of carcasses. It is desirable to process the carcasses and move the carcasses to the chill room as soon as possible after slaughter to decrease the chances of increased microbial growth.
There is a need in the art for methods and devices for improving the processing of carcasses in slaughterhouses that are commercially practical, relatively simple to implement, and improve the processing rate of carcasses and the effectiveness of the carcass inspection.